With rapid development of electronic and information industries, computers and the peripheral device thereof become essential parts in our daily lives. In addition to the working purposes, computers can be employed as amusement tools. In the computer systems, input devices play important roles for communicating the computer with the user. The common input devices of the computer systems include for example mice, keyboards or trackballs.
As know, keyboards have the most keys among the common input devices. Hereinafter, the configurations of a conventional keyboard will be illustrated with reference to FIG. 1. FIG. 1 is a schematic view illustrating the outward appearance of a conventional keyboard. There are plural keys mounted on the surface of the keyboard 1. These keys include for example ordinary keys 10, numeric keys 11 and function keys 12. When one or more keys are depressed by the user, a corresponding signal is issued to the computer, and thus the computer executes a function corresponding to the depressed key or keys. For example, when the ordinary keys 10 are depressed, corresponding English letters or symbols are inputted into the computer system. In addition, the function keys 12 (F1˜F12) can be programmed to cause corresponding application programs to provide certain functions.
Generally, in the fabricating process of the keyboard, a testing method should be performed to realize whether the functions of the keyboard are normal or not. The testing method includes a step of testing the circuit board of the keyboard and a step of testing the overall functions of the assembled keyboard. By testing the circuit board, the manufacturer may realize whether any defects are present in the circuit board. If the step of testing the circuit board is eliminated, after the keyboard device is assembled and some defects are found, the keyboard needs to be disassembled to debug the circuit board. It is troublesome and time-consuming to disassemble the keyboard device and debug the circuit board.
Hereinafter, the internal circuitry of a conventional keyboard will be illustrated with reference to FIG. 2. FIG. 2 is a schematic circuit diagram illustrating the internal circuitry of a conventional keyboard. The keyboard 1 includes a circuit board (not shown), a microprocessor 13 and a keyboard scanning matrix 14. The microprocessor 13 is connected with the keyboard scanning matrix 14. The other parts of the microprocessor 13 are known in the art, and are not redundantly described herein. In addition, the keyboard scanning matrix 14 comprises plural scan input lines X0˜X7 and plural scan output lines Y0˜Y17, which crisscross with each other. The scan input lines X0˜X7 have respective first terminals connected with the microprocessor 13. In addition, the scan input lines X0˜X7 have respective second terminals connected with corresponding input pins (not shown) of the circuit board. The scan output lines Y0˜Y17 have respective first terminals connected with the microprocessor 13. In addition, the scan output lines Y0˜Y17 have respective second terminals connected with corresponding output pins (not shown) of the circuit board. Since the keyboard scanning matrix 14 includes 8 scan input lines (X0˜X7) and 18 scan output lines (Y0˜Y17), the keyboard scanning matrix 14 is an 8×18 scanning matrix. Each scan input line and each scan output line crisscross to define an intersection. In other words, the keyboard scanning matrix 14 has a total of 144 intersections correlating with 144 keys on the surface of the keyboard device 1. That is, in a case that the keyboard 1 has 144 keys, the internal circuitry of keyboard 1 should at least comprise 8 scan input lines and 18 scan output lines.
Hereinafter, a conventional method of testing the circuit board of the keyboard will be illustrated with reference to FIG. 2. After the circuit board of the keyboard is produced, the circuit board is connected with a testing module. The testing module includes 26 switches and 26 light emitting diodes (LEDs). These 26 switches are respectively connected with the input pins corresponding to the scan input lines X0˜X7 and the output pins corresponding to the scan output lines Y0˜Y17. These 26 light emitting diodes correspond to the 26 switches. Then, these 26 switches are manually depressed one by one. If the light emitting diode connected with the depressed switch illuminates, it means that the input pin or the output pin corresponding to the depressed switch passes the test. On the other hand, if the light emitting diode connected with the depressed switch does not illuminate, it means that the function of the input pin or the output pin corresponding to the depressed switch is abnormal. In other words, the operator may judge whether the function of the circuit board is normal according to the illuminating statuses of the light emitting diodes.
Although the convention method for testing the circuit board is simple, there are still some drawbacks. For example, it is time-consuming and labor-intensive to successively depress the switches. Since too many keys need to be manually tested, the operator may repeatedly depress the same keys or forger to depress some keys. Under this circumstance, the testing method should be performed again, so that manual testing method is ineffective and costly.
For solving the above problems, an automatic testing system for testing the circuit board of the keyboard. In this circuit board testing system, a pin test script specifically applied to a circuit board with a certain scanning matrix format (e.g. an 8×18 scanning matrix format) has been previously written. According to the pin test script, a test program is executed to test the circuit board. In such way, the possibility of erroneously depressing the switches by the manual testing method will be minimized. However, this circuit board testing system is only applied to the circuit board with the certain scanning matrix format (e.g. the 8×18 scanning matrix format). For testing the circuit board with another scanning matrix format (e.g. an 8×16 scanning matrix format), the original pin test script of this circuit board testing system should be modified, or another pin test script specifically applied to the circuit board with the 8×16 scanning matrix format should be written.
Moreover, the pin settings of the circuit board to be tested by the circuit board testing system should be defined. For example, the intersection corresponding to the first input pin and the first output pin is defined as the key A. If the pins settings of a circuit board to be tested do not comply with the specifications of the pin test script of this circuit board testing system, the original pin test script should be modified in order to test the circuit board.
Therefore, there is a need of providing a circuit board testing system for testing circuit boards with various scanning matrix formats and testing circuit boards with various pin settings.